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Australopithecus

Identifying the earliest member of the human tribe (Hominini) is difficult because the predecessors of modern humans are increasingly apelike as the fossil record is followed back through time. They resemble what would be expected in the common ancestor of humans and apes in that they possess a mix of human and ape traits. For example, the earliest species,
S. tchadensis, is humanlike in...

There appear to be two major structural shifts in the evolution of the human body. The first was the transition to bipedalism that is documented in
A. anamensis,
A. afarensis,
A. africanus, and
A. garhi, which span a time frame from 4.2 to 2.5 mya. The limbs and torsos among these species are difficult to assess because of the incompleteness of the fossil record. All...

human evolution

...
Ardipithecus include an increased tarsal region in each foot and a pelvic structure with muscle-to-bone attachment sites comparable to later, bipedal hominins. In addition, the leg bone of
Australopithecus anamensis from northern Kenya (4.2–3.9 mya) attests to its bipedalism.

...habitat. Later remains, in northern Ethiopia, indicate
Australopithecus afarensis inhabited a mosaic of riverine forest, lowland woodland, savanna, and dry bushland. In northern Kenya
Australopithecus anamensis lived in dry open woodland or bushland with a gallery forest along a nearby river. In central Chad the northernmost and westernmost species,
Australopithecus...

Kanapoi excavation

site of paleoanthropological excavations in northern Kenya southwest of Lake Turkana (Lake Rudolf), best known for its fossils of
Australopithecus anamensis, an early hominin (member of the human lineage) dating to between 3.9 and 4.2 million years ago. Among these fossils is a relatively complete shinbone with features indicating that
A. anamensis walked on two...